XML 105 R88.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Regulatory Matters (Narrative) (Detail) $ in Millions |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Feb. 01, 2020 | Oct. 31, 2018 USD ($) program MMcf | Sep. 30, 2018 USD ($) kV mi | Aug. 31, 2018 USD ($) project MW kV mi | Jul. 31, 2018 USD ($) | May 31, 2018 USD ($) | Aug. 31, 2009 kV | Apr. 30, 2007 kV | Jun. 30, 2018 USD ($) | Jun. 30, 2017 USD ($) | Sep. 30, 2018 USD ($) | Jan. 31, 2020 | Dec. 31, 2017 USD ($)
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory assets-noncurrent |  |  |  | $ 2,316 |  |  |  |  |  |  |  | $ 2,316 |  | $ 2,480 | [1]
Regulatory asset recovered through retail rates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory assets-noncurrent | [2] |  |  | 265 |  |  |  |  |  |  |  | 265 |  | 222 |
Virginia Regulation | Operating Segments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Charge associated with legislation |  |  |  |  |  |  |  |  |  |  |  | 215 |  |  |
Charge associated with legislation, after tax |  |  |  |  |  |  |  |  |  |  |  | 160 |  |  |
Virginia Electric and Power Company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory assets-noncurrent |  |  |  | 636 |  |  |  |  |  |  |  | 636 |  | 810 | [3]
Tax reform benefit |  |  |  |  | $ 100 |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in regulatory liabilities |  |  | $ 14 |  |  |  |  |  |  |  |  |  |  |  |
Regulatory liabilities one time bill credit amount |  |  | 13 |  |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Regulatory asset recovered through retail rates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory assets-noncurrent | [2] |  |  | 265 |  |  |  |  |  |  |  | $ 265 |  | $ 222 |
Virginia Electric and Power Company | Virginia Regulation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interim rate reduction amount |  |  |  |  |  | $ 125 |  |  |  |  |  |  |  |  |
Estimated recovery of fuel expenses |  |  |  |  |  |  | $ 1,500 |  |  |  |  |  |  |  |
Increase in fuel revenue |  |  |  |  | $ 209 |  | 222 |  |  |  |  |  |  |  |
Earnings above authorized return on equity (basis points) |  |  |  |  |  |  |  |  |  |  |  | 70.00% |  |  |
One-time bill credit, provisions for current customers |  |  |  |  |  |  |  |  |  |  |  | $ 200 |  |  |
Charge associated with legislation |  |  |  |  |  |  |  |  |  |  |  | 215 |  |  |
Charge associated with legislation, after tax |  |  |  |  |  |  |  |  |  |  |  | 160 |  |  |
Legislation amount credited in customer bill |  |  |  |  |  |  |  |  |  |  |  | 138 |  |  |
Virginia Electric and Power Company | Virginia Regulation | Coastal Virginia Offshore Wind Project |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capacity of wind turbine generators (mV) | MW |  |  |  |  | 6 |  |  |  |  |  |  |  |  |  |
Public utilities length of wind project | mi |  |  |  |  | 27 |  |  |  |  |  |  |  |  |  |
Total estimated cost of project |  |  |  |  | $ 300 |  |  |  |  |  |  |  |  |  |
Number of wind projects | project |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Transmission Line Between Lanexa and Dunnsville Substations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total estimated cost of project |  |  |  |  | $ 15 |  |  |  |  |  |  |  |  |  |
Capacity of transmission line (kV) | kV |  |  |  |  | 138 |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Transmission Line Between Dooms Substation and Valley Substation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total estimated cost of project |  |  |  | $ 65 |  |  |  |  |  |  |  | 65 |  |  |
Capacity of transmission line (kV) | kV |  |  |  | 500 |  |  |  |  |  |  |  |  |  |  |
Length of kV line (miles) | mi |  |  |  | 18 |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Transmission Line Between Idylwood and Tysons Substations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total estimated cost of project |  |  |  | $ 125 |  |  |  |  |  |  |  | 125 |  |  |
Capacity of transmission line (kV) | kV |  |  |  | 230 |  |  |  |  |  |  |  |  |  |  |
Length of kV line (miles) | mi |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Operating Segments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Charge associated with legislation |  |  |  |  |  |  |  |  |  |  |  | 215 |  |  |
Charge associated with legislation, after tax |  |  |  |  |  |  |  |  |  |  |  | 160 |  |  |
Proposed revenue requirement |  |  |  |  | $ 636 |  | 755 |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Operating Segments | Transmission Component of Virginia Power's |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed revenue requirement |  |  |  |  |  |  | 468 |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed annual revenue reduction amount |  |  | 151 |  |  |  |  |  |  |  |  |  |  |  |
Estimated annual revenue reduction on one-time bill credit |  |  | $ 95 |  |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Riders C1A and C2A | Subsequent Event | Operating Segments | Energy Efficiency Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of new energy efficiency programs | program |  |  | 10 |  |  |  |  |  |  |  |  |  |  |  |
Period for cost cap |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |
Number of new demand response programs | program |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |
Amount of cost recovery |  |  | $ 262 |  |  |  |  |  |  |  |  |  |  |  |
Proposed revenue requirement |  |  | 49 |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in revenue requirement |  |  | 18 |  |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Rider BW | Subsequent Event | Operating Segments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed revenue requirement |  |  | 123 |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in revenue requirement |  |  | 7 |  |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Rider US-2 | Subsequent Event | Operating Segments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed revenue requirement |  |  | 16 |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in revenue requirement |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Virginia Regulation | Rider T1 | Operating Segments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed revenue requirement |  |  |  |  | 630 |  | 287 |  |  |  |  |  |  |  |
Increase (decrease) in revenue requirement |  |  |  |  |  |  | 146 |  |  |  |  |  |  |  |
Virginia Electric and Power Company | North Carolina Regulation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed cost increase (decrease) amount |  |  |  |  | $ 24 |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | North Carolina Regulation | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mitigation recoverable percentage |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |
Mitigation recoverable remaining percentage |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Settled Litigation | Federal Energy Regulatory Commission | Order Regarding Transmission Rate Design For Allocation Of Costs Among P J M Interconnect L L C Transmission Customers | Unfavorable Regulatory Action |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Duration of payment under settlement agreement |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |
Amount required to pay under settlement agreement |  |  |  |  | $ 276 |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Settled Litigation | Federal Energy Regulatory Commission | Order Regarding Transmission Rate Design For Allocation Of Costs Among P J M Interconnect L L C Transmission Customers | Unfavorable Regulatory Action | Other Current Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of contingent liability |  |  |  | $ 170 |  |  |  |  |  |  |  | 170 |  |  |
Virginia Electric and Power Company | Settled Litigation | Federal Energy Regulatory Commission | Order Regarding Transmission Rate Design For Allocation Of Costs Among P J M Interconnect L L C Transmission Customers | Unfavorable Regulatory Action | Other Deferred Credits and Other Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of contingent liability |  |  |  | 72 |  |  |  |  |  |  |  | $ 72 |  |  |
Virginia Electric and Power Company | Settled Litigation | Federal Energy Regulatory Commission | Order Regarding Transmission Rate Design For Allocation Of Costs Among P J M Interconnect L L C Transmission Customers | Unfavorable Regulatory Action | Regulatory asset recovered through retail rates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory assets-noncurrent |  |  |  |  | $ 265 |  |  |  |  |  |  |  |  |  |
Virginia Electric and Power Company | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Facility operating capacity (kV) | kV |  |  |  |  |  |  |  |  | 500 |  |  |  |  |  |
Virginia Electric and Power Company | Minimum | Judicial Ruling [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Facility operating capacity (kV) | kV |  |  |  |  |  |  |  | 500 |  |  |  |  |  |  |
DETI | Federal Energy Regulatory Commission | Other operations and maintenance | Preliminary recommendation one |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Audit compliance charge recognized in connection with preliminary recommendation |  |  |  |  |  |  |  |  |  |  | $ 15 |  |  |  |
Audit compliance after-tax charge recognized in connection with preliminary recommendation |  |  |  |  |  |  |  |  |  |  | $ 9 |  |  |  |
DETI | Federal Energy Regulatory Commission | Other operations and maintenance | Other preliminary recommendation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Audit compliance charge recognized in connection with preliminary recommendation |  |  |  |  |  |  |  |  |  | $ 129 |  |  |  |  |
Audit compliance after-tax charge recognized in connection with preliminary recommendation |  |  |  |  |  |  |  |  |  | $ 94 |  |  |  |  |
Questar Gas | Cost-of-service impact of 2017 Tax Reform Act |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in regulatory liabilities |  |  |  |  |  |  | $ 15 |  |  |  |  |  |  |  |
Corporate income tax reduction to customer |  |  |  |  |  | $ 9 |  |  |  |  |  |  |  |  |
Regulatory liability, amortization period |  |  |  |  |  |  | 1 year |  |  |  |  |  |  |  |
Questar Gas | Utah and Wyoming Regulation | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proposed cost increase (decrease) amount |  |  | $ 48 |  |  |  |  |  |  |  |  |  |  |  |
LNG peaking storage facility, liquefaction rate per day | MMcf |  |  | 8.2 |  |  |  |  |  |  |  |  |  |  |  |
East Ohio | Ohio Regulation | UEX Rider |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Elimination of over-recovered balance of accumulated bad debt expense |  |  |  | 11 |  |  |  |  |  |  |  |  |  |  |
Prospective bad debt expense recovered |  |  |  | $ 16 |  |  |  |  |  |  |  |  |  |  |
[1] | Dominion Energy’s Consolidated Balance Sheet at December 31, 2017 has been derived from the audited Consolidated Balance Sheet at that date.
[2] | Reflects amounts related to the PJM transmission cost allocation matter. See Note 13 for more information.
[3] | Virginia Power’s Consolidated Balance Sheet at December 31, 2017 has been derived from the audited Consolidated Balance Sheet at that date.

X
- Definition Audit compliance after-tax charge with accounting and reporting requirements recognized. + References No definition available. + Details
Name: | d_AuditComplianceAfterTaxChargeWithAccountingAndReportingRequirementsRecognized
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Audit compliance charge with accounting and reporting requirements recognized. + References No definition available. + Details
Name: | d_AuditComplianceChargeWithAccountingAndReportingRequirementsRecognized
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Corporate income tax reduction refund to customer. + References No definition available. + Details
Name: | d_CorporateIncomeTaxReductionRefundToCustomer
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Estimated annual revenue reduction on one-time bill credit. + References No definition available. + Details
Name: | d_EstimatedAnnualRevenueReductionOnOneTimeBillCredit
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Kilo Volt Line + References No definition available. + Details
Name: | d_KiloVoltLine
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Legislation amount credited in customer bill. + References No definition available. + Details
Name: | d_LegislationAmountCreditedInCustomerBill
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Legislation charge. + References No definition available. + Details
Name: | d_LegislationCharge
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Legislation charge after tax. + References No definition available. + Details
Name: | d_LegislationChargeAfterTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Liquefied natural gas peaking storage facility liquefaction rate per day. + References No definition available. + Details
Name: | d_LiquefiedNaturalGasPeakingStorageFacilityLiquefactionRatePerDay
Namespace Prefix: | d_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loss contingency, settlement agreement, duration of settlement payment. + References No definition available. + Details
Name: | d_LossContingencySettlementAgreementDurationOfSettlementPayment
Namespace Prefix: | d_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Mega volt line. + References No definition available. + Details
Name: | d_MegaVoltLine
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Mitigation recoverable percentage. + References No definition available. + Details
Name: | d_MitigationRecoverablePercentage
Namespace Prefix: | d_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Mitigation recoverable remaining percentage. + References No definition available. + Details
Name: | d_MitigationRecoverableRemainingPercentage
Namespace Prefix: | d_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of wind projects. + References No definition available. + Details
Name: | d_NumberOfWindProjects
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition One-time bill credit, provisions for current customers. + References No definition available. + Details
Name: | d_OneTimeBillCreditProvisionsForCurrentCustomers
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Phase-in plan, amount of capitalized costs recoverable. + References No definition available. + Details
Name: | d_PhaseInPlanAmountOfCapitalizedCostsRecoverable
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public utilities annual revenue reduction amount. + References No definition available. + Details
Name: | d_PublicUtilitiesAnnualRevenueReductionAmount
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Excess Percentage above Authorized Return on Equity + References No definition available. + Details
Name: | d_PublicUtilitiesExcessPercentageAboveAuthorizedReturnOnEquity
Namespace Prefix: | d_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities interim rate reduction amount. + References No definition available. + Details
Name: | d_PublicUtilitiesInterimRateReductionAmount
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Public utilities, length of transmission line. + References No definition available. + Details
Name: | d_PublicUtilitiesLengthOfTransmissionLine
Namespace Prefix: | d_
Data Type: | num:lengthItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities length of wind project. + References No definition available. + Details
Name: | d_PublicUtilitiesLengthOfWindProject
Namespace Prefix: | d_
Data Type: | num:lengthItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities number of new demand response programs. + References No definition available. + Details
Name: | d_PublicUtilitiesNumberOfNewDemandResponsePrograms
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities, number of new energy efficiency programs. + References No definition available. + Details
Name: | d_PublicUtilitiesNumberOfNewEnergyEfficiencyPrograms
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities operating expense estimated fuel expenses recovery. + References No definition available. + Details
Name: | d_PublicUtilitiesOperatingExpenseEstimatedFuelExpensesRecovery
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public utilities, operation capacity of transmission facilities. + References No definition available. + Details
Name: | d_PublicUtilitiesOperationCapacityOfTransmissionFacilities
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities, period for cost capitalization. + References No definition available. + Details
Name: | d_PublicUtilitiesPeriodForCostCapitalization
Namespace Prefix: | d_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Public utilities, property, plant and equipment, expected cost of construction. + References No definition available. + Details
Name: | d_PublicUtilitiesPropertyPlantAndEquipmentExpectedCostOfConstruction
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Public utilities requested cost increase decrease amount. + References No definition available. + Details
Name: | d_PublicUtilitiesRequestedCostIncreaseDecreaseAmount
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Public Utilities, Requested Rate, Amount + References No definition available. + Details
Name: | d_PublicUtilitiesRequestedRateAmount
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Regulatory liabilities one time bill credit amount. + References No definition available. + Details
Name: | d_RegulatoryLiabilitiesOneTimeBillCreditAmount
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Tax reform benefit. + References No definition available. + Details
Name: | d_TaxReformBenefit
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of recoveries of receivables doubtful of collection that were previously charged off. + References No definition available. + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of direct write-downs of accounts receivable charged against the allowance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The increase (decrease) during the reporting period in regulated liabilities. Regulated liabilities are created when regulatory agency permits an entity to defer revenues to the balance sheet. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
Name: | us-gaap_IncreaseDecreaseInRegulatoryLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount awarded to other party in judgment or settlement of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of loss contingency liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
Name: | us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesGeneralDisclosuresLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesInterimRateIncreaseDecreaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssetsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortization period for the recovery of regulatory liability, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_RegulatoryLiabilityAmortizationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=d_TransmissionRateDesignForAllocationOfCostsOfServiceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=d_VirginiaRegulationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=d_VirginiaElectricAndPowerCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_CoastalVirginiaOffshoreWindProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_TransmissionLineBetweenLanexaAndDunnsvilleSubstationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_TransmissionLineBetweenDoomsSubstationAndValleySubstationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_TransmissionLineBetweenIdylwoodAndTysonsSubstationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_TransmissionComponentOfVirginiaPowersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_RidersC1AAndC2AMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=d_EnergyEfficiencyProgramMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_RiderBWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_RiderUS2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_RiderT1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=d_NorthCarolinaRegulationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LitigationStatusAxis=us-gaap_SettledLitigationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=d_FederalEnergyRegulatoryCommissionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=d_OrderRegardingTransmissionRateDesignForAllocationOfCostsAmongPJMInterconnectLLCTransmissionCustomersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_UnfavorableRegulatoryActionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_OtherCurrentLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=d_OtherDeferredCreditsAndOtherLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LitigationStatusAxis=us-gaap_JudicialRulingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=d_DominionEnergyTransmissionIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=d_OtherOperationsAndMaintenanceExpenseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_PreliminaryRecommendationOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_OtherPreliminaryRecommendationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=d_QuestarGasCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=d_CostOfServiceImpactOf2017TaxReformActMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=d_UtahAndWyomingRegulationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=d_EastOhioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=d_OhioRegulationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=d_UncollectibleExpenseRiderMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |